[2657] Luo Gu windy number

Title Description

windy defines a number windy. Without leading zeros and adjacent to at least the difference between two numbers is called a positive integer number windy. windy want to know,

Between A and B, including A and B, total number of windy number?

Input Format

It contains two integers, AB.

Output Format

An integer

Sample input and output

Input # 1copy

1 10

Output # 1copy

9

Input # 2copy

25 50

Output # 2copy

20

Description / Tips

100% data satisfies 1 <= A <= B <= 2000000000.

 

Solution: dp digital solution, provided dp [i] [J] of length i is the number of bits in the highest number of windy j

Equation dp [i] [j] = sum (dp [i-1] [k]), such a transfer is transferred from the former and by

#include<cstdio>
#include<iostream>
#include<cmath>
#include<cstdlib>
#include<cstring>
#include<algorithm>
typedef long long ll;
using namespace std;
int f[22][22],a[22];
void Cang_Shu_Xia(){
    for(int i=0;i<=9;i++)
        f[1][i]=1;
    for(int i=2;i<=10;i++)
        for(int j=0;j<=9;j++)
            for(int k=0;k<=9;k++)
                if(abs(j-k)>=2) 
                   f[i][j]+=f[i-1][k];
}
int len,ans;
int Yao_Chen_Lai_Le(int x){
    memset(a,0,sizeof(a));
    len=0; ans=0;
    while(x){
        a[++len]=x%10;
        x/=10;
    }
    for(int i=1;i<len;i++)
        for(int j=1;j<=9;j++)
            ans+=f[i][j];
    for(int i=1;i<a[len];i++)
        ans+=f[len][i];
    for(int i=len-1;i>=1;i--){
        for(int j=0;j<=a[i]-1;j++) 
            if(abs(j-a[i+1])>=2)    
               ans+=f[i][j];
        if(abs(a[i+1]-a[i])<2)       
           break;
    }
    return ans;
}
int main(){
    freopen("2657.in","r",stdin);
    freopen("2657.out","w",stdout);
    
    Cang_Shu_Xia();
    int n,m;  cin>>n>>m;
    cout<<Yao_Chen_Lai_Le(m+1)-
          Yao_Chen_Lai_Le(n);
    return 0;
}